A diminished chord on piano (Adim)
Adim is A, C and E♭. A is the white key between the last two black keys of the three. Play it once at full speed, then at a quarter to hear every note.
root position · A–C–E♭ · right hand 1-3-5
- Notes
- A · C · E♭
- Formula
- 1 · ♭3 · ♭5
How to play Adim on piano
Start on A, count 3 half steps up to C then 3 half steps up to E♭. Those 3 keys are Adim.
- Right hand: 1 on A, 3 on C and 5 on E♭.
- Left hand: 5 on A, 3 on C and 1 on E♭.
- On the keyboard it's white, white and black keys, the same pattern as Ddim and Edim, so your hand shape carries over.
Adim inversions
- root position: A–C–E♭. Right hand 1-3-5.
- 1st inversion: C–E♭–A, C lowest. RH 1-2-5.
- 2nd inversion: E♭–A–C, with E♭ at the bottom. RH 1-3-5.
Nobody plays every chord in root position. The inversions let Adim sit wherever the previous chord left your hand.
Changing from Adim to the chords around it
The chords Adim usually goes to, and what changes under your fingers.
- B♭ (leads up a half step): Adim to B♭: play B♭ in root position (B♭–D–F), while A moves up to B♭, C up to D and E♭ up to F. B♭ on piano
- B♭m (leads up a half step): Adim to B♭m: play B♭m in root position (B♭–D♭–F), while A moves up to B♭, C up to D♭ and E♭ up to F. B♭m on piano
- Dm (iii in B♭ major): Adim to Dm: play Dm in 2nd inversion (A–D–F) and A stays under the same finger, while C moves up to D and E♭ up to F. Dm on piano
Adim is a diminished triad: two minor thirds stacked. Adim rarely stays long; it's a passing chord that usually climbs a half step to the next chord. The one-by-one button above makes that quality easy to hear.
Getting Adim under your fingers
Roll the chord up and back down, A, C, E♭, C, A, before playing it as a block. Next, walk up through A–C–E♭ → C–E♭–A → E♭–A–C without lifting your eyes to your hand.
The keys of Adim
Adim is a diminished chord, 1–♭3–♭5 from A. Root position, from the bottom: how Adim is built.
| Note | Key | Fingers | Role |
|---|---|---|---|
| A | white key | RH 1 · LH 5 | root |
| C | white key | RH 3 · LH 3 | minor third |
| E♭ | black key | RH 5 · LH 1 | diminished fifth |
Adim in context
Adim on guitar and ukulele
Adim on guitar and ukulele uses the same 3 notes in a different layout. See all three together.
Related A chords on piano
Other diminished chords
Adim on piano: questions
What notes are in Adim on piano?
A, C and E♭: A (white key), C (white key) and E♭ (black key). Right hand 1-3-5, left hand 5-3-1.
How do you play Adim on piano?
Press A, C and E♭ together (1 black, 2 white). Right hand: 1 on A, 3 on C and 5 on E♭.
What are the inversions of Adim?
1st inversion (C–E♭–A) and 2nd inversion (E♭–A–C), after root position (A–C–E♭). Only the lowest note changes.
What does Adim look like on the keyboard?
white, white and black keys, the same pattern as Ddim and Edim, so one hand shape covers all of them.
Checked automatically: no shape here plays a note outside Adim. Updated September 2026.